Windows explorer does not start when second monitor is connected

Recently, I decided it might be a good idea to connect my old monitor - an Acer P2432w - to my windows 10 system as a secondary monitor. I will call it monitor B from now on. My primary monitor (monitor A) is an UHD monitor and connected via display port. Monitor B's resolution is 1920 * 1280 and I connected it using HDMI or DVI connection.

The problem is: As soon as I connect monitor B (i.e. plug in the monitor cable), I am no longer able to start a new windows explorer. It just does not open.

Instances of explorer which are already open before I connected monitor B remain open and keep working properly. But all open explorers crash as soon as I try to start a new instance of explorer while Monitor B is connected (other apps stay open) and as explained, new instances of explorer will not start any more.

On my windows 10 system, I use 3 accounts. Two without admin priviledges and one admin account. The problem does not occur on the admin account.

The problem even occurs when I unplug the power cable from the monitor. The only solution is to unplug the HDMI or DVI cable from monitor B in order to start new windows explorers again.

The driver for my graphics card (NVIDIA GeForce GTX 970) is up to date. In addition to the display port connection, my graphics card has two DVI ports and on HDMI port. The problem with the second monitor occurs on each 3 of them. (Monitor A is always connected to the display port)

I already performed a complete system restore which had no effect. So the windows system does not seem to be corrupted, the problem just always occurs when the second monitor is connected and disappears as soon as it is disconnected.

Any help would be appreciated.

Summary of my system:

• OS: Windows 10, 64 Bit
• Graphics card: NVIDIA GeForce GTX 970
• Graphics driver: Date: 2015-12-16, version 10.18.13.6143
• Primary montitor: Samsung U28D590D, resolution UHD, connection: display port
• Secondary monitor: Acer P243w, resolution HD, connection: HDMI or DVI

Here are two error messages of the windows event log (german system):

Name der fehlerhaften Anwendung: explorer.exe, Version: 10.0.10586.0, Zeitstempel: 0x5632d4c0
Name des fehlerhaften Moduls: comctl32.dll, Version: 6.10.10586.0, Zeitstempel: 0x5632d2ce
Ausnahmecode: 0xc000041d
Fehleroffset: 0x000000000003c3e2
ID des fehlerhaften Prozesses: 0x2d50
Startzeit der fehlerhaften Anwendung: 0x01d14ba6e6d514c4
Pfad der fehlerhaften Anwendung: C:\WINDOWS\explorer.exe
Pfad des fehlerhaften Moduls: C:\WINDOWS\WinSxS\amd64_microsoft.windows.common-controls_6595b64144ccf1df_6.0.10586.0_none_8c15ae12515e1c22\comctl32.dll
Berichtskennung: 3f5cf376-9f30-4992-9fd3-fd686630abcf
Vollständiger Name des fehlerhaften Pakets: 
Anwendungs-ID, die relativ zum fehlerhaften Paket ist:

Name der fehlerhaften Anwendung: explorer.exe, Version: 10.0.10586.0, Zeitstempel: 0x5632d4c0
Name des fehlerhaften Moduls: USER32.dll, Version: 10.0.10586.20,   Zeitstempel: 0x565423d2
Ausnahmecode: 0xc000041d
Fehleroffset: 0x000000000000e747
ID des fehlerhaften Prozesses: 0x1c98
Startzeit der fehlerhaften Anwendung: 0x01d14ba2cf7a4d44
Pfad der fehlerhaften Anwendung: C:\WINDOWS\explorer.exe
Pfad des fehlerhaften Moduls: C:\WINDOWS\system32\USER32.dll
Berichtskennung: 675c4997-56d0-424c-9046-39bb7f8a8f31
Vollständiger Name des fehlerhaften Pakets: 
Anwendungs-ID, die relativ zum fehlerhaften Paket ist: 

Explorer chrashdump files

Here is a link to windows eplorer crashdump files, creating using the Windows Error Reporting Service (Thanks for the tip @magicandre1981):

Link to Crashdumps (shared one drive folder)

ok, I got an answer from Microsoft. They know this issue and currently work on it.

This crash happens if the 2 monitors use different DPI scaling (they know it crashes with 175% on 1 and 100% on the other monitor). You should change the 175% to 150% or 200% to workaround it. Maybe this helps. Try it out.